September 28, 2008

The US Coast Guard has announced that it has finally settled on a patrol boat design to replace its aging 110 foot "Island Class" patrol boats. It appears that they have made a very good choice.

Behold! the Sentinel class, 153 foot patrol boats.

A very modern off the shelf design, the vessel has been in service with the Dutch Coast Guard for several years. The Dutch area of operations ranges from the North Sea to their colonies in the Caribbean and so is a pretty good match for the USCG's needs.

The vessel is robust, steel hulled, lightly ice strengthened and considered seaworthy enough that a version of these vessels was recently been put into service with the South African Coast Guard, where its patrol area includes the violent seas around Cape Agulhas and parts of the Southern Ocean. A version is also in service with the UK's customs service.

In other words...the design has been vetted!

NO SURPRISES THIS TIME!

It looks really cool too....

Interestingly it will be built at Bollinger, which has given the US Coast Guard a generally good customer experience in the past and has built many of the patrol boats in service with the Navy and the Coast Guard. Between 34 and 58 of these vessels are planned.

The vessel is quite heavily armed for a Coast Guard cutter with 4x.50 caliber machine guns and a 25mm chain gun. Stern launch systems are exceedingly convenient and safe, but because of their location and the need for a large hole in the structure, they have caused some structural issues and had teething problems.However, this stern launching system is in service with both the closely related Dutch and UK versions of the design. Thus, it has been through its "learning experience" phase. Thus there should be minimal issues with it.

After the delays, disappointments and disasters involving procurement, this is a very heartening decision.

What kind of ammunition do you think they'd carry for "routine" use of that 25mm chaingun? Looking at the linked article, the choices seem to be HEI (I assume "high explosive incendiary"?) and APDS ("armor piercing discarding sabot") and I'm inclined to think that APDS would be their ammo of choice, since that's what they'd need if they were shooting up a steel-hulled ship. It seems to me that HEI would just bounce.

3
Presumably if a FRC is firing in earnest at something, it's going to be
some kind of small speed/gunboat full of pirates or explosives as a not-so-smart bomb. If the need arises to fire at something larger, a few rounds in the bridge area would be the order of the day. In those cases, HEI is plenty dangerous, in fact probably more so than a small armor piercing round, from the incendiary effect.

The article doesn't say under what terms the design was aquired, I presume it wasn't just freely available to any interested shipyard. Do you know how something like that is normally done, or have you seen an article that described how it was done for this deal?

A last interesting bit.. that list of expected duties from the FRC faq is pretty comprehensive. Is there any CG duty other than ice breaking that isn't on that list?

Posted by: David at Mon Sep 29 02:51:23 2008 (UpR/+)

4
In the rare cases that the cannon is used for something other than a shot across the bow, I would guess that non explosive rounds would be used for disabling fire damaging the rudder, screw or firing into the engine). This would minimize but not eliminate collateral damage. If the target is pirates, then I would suppose explosive rounds are best.

Note that I'm not a gunners mate and If I knew what I was talking about I probably couldn't discuss it.

A last interesting bit.. that list of expected duties from the FRC faq
is pretty comprehensive. Is there any CG duty other than ice breaking
that isn't on that list?

The vessel seems ill equipped for any buoy tending aside from changing bulbs and solar panels. It's not really suited for the western rivers either. Both require highly specialized vessels.